April 09, 2025 | Postharvest Biology and Technology |
The cause of postharvest fruit rot in longan (Dimocarpus longan Lour.), which significantly affects the fruit’s marketability and trade, was the focus of a study conducted by researchers from Nanjing Agricultural University, China. In 2023, a notable outbreak of fruit rot was observed in Guangdong Province, with an estimated disease incidence of 25%.
Morphological characteristics and molecular analysis identified Aspergillus aculeatus as the causal agent, marking the first report of this species causing fruit rot in longan. Pathogenicity tests confirmed that the isolated strains maintained high virulence. Infection with A. aculeatus led to increased enzymatic activity of polygalacturonase, pectinase, cellulase, and β-galactosidase, resulting in the degradation of key cell wall components such as pectin, cellulose, and hemicellulose. This enzymatic breakdown contributes directly to fruit tissue decay.
Among several tested fungicides, fludioxonil showed the highest efficacy against A. aculeatus, with an EC₅₀ of 0.0170 ± 0.0006 µg/mL and more than 75% control effectiveness in vivo. The study recommends fludioxonil for managing this pathogen and highlights the need for fungicide rotation strategies to delay resistance development. These findings provide a foundation for improving postharvest disease control in longan and supporting sustainable fruit industry practices.
